Disk files are information storage devices which utilize at least one rotatable disk with concentric data tracks containing the information, a head (or "transducer") for reading data from or writing data to the various tracks, and a head positioning actuator connected to the head for moving it to the desired track and maintaining it over the track centerline during read or write operations. The transducer is attached to an air-bearing slider which is supported adjacent the data surface of the disk by a cushion of air generated by the rotating disk. The slider is connected to a support arm of the head positioning actuator by means of a suspension.
The suspension provides high spring stiffness and dimensional stability between the slider and actuator arm, some flexibility in pitch and roll motion of the slider relative to its direction of motion to the rotating disk, and resistance to yaw motion. In certain disk files the suspension provides a load or force against the slider which is compensated by the force of the air bearing between the slider and the disk, thus maintaining the slider in extremely close proximity to, but out of contact with, the data surface of the disk. Other types of disk files utilize a "negative pressure" or "self-loading" slider, such as is disclosed in U.S. Pat. No. 3,855,625 assigned to the same assignee as this application. It is desirable to maintain the self-loading slider adjacent the data surface of the disk with as low a "loading" force as possible since the slider creates a vacuum between it and the disk which holds the slider adjacent the data surface.
Conventional slider-suspension assemblies have several inherent disadvantages. First, because some load is typically applied to the slider by the suspension in a generally perpendicular direction relative to the data surface of the disk, the slider comes to rest on the data surface of the disk when disk rotation stops and the air bearing disappears. The starting and stopping of the disk with the slider in contact can cause damage to the data surface of the disk and to the slider or attached transducer. If it is desired to maintain the slider away from the disk when the disk is not rotating, it is necessary to use some type of "load/unload" device which mechanically moves the suspension and/or slider away from the disk when disk rotation stops and back to the disk when the disk has reached its operating speed and the air bearing is present to maintain the slider out of contact with the data surface. Secondly, because conventional suspensions are designed to flex in a generally perpendicular direction relative to the data surface of the disk and are thus not generally rigid in that direction, the data surface of the disk and the slider can be damaged if the slider suddenly impacts the disk, such as may occur during shipping of the disk file.